Alec plans a dinner to propose to Magnus.
Clary visits Jonathan and demands answers about the Morgenstern Sword. In a flashback, Jonathan relives the moment Lilith told him about Clary.
Isabelle makes a plan to sneak Simon into "Project Heavenly Fire" in hopes of finding Glorious, which could destroy Clary's connection to Jonathan.
Simon finds Raphael who is also being held in the facility. Isabelle reaches out to Simon using their Seelie rings to communicate telepathically.
Isabelle tries to convince Aline to help her figure out Simon's location. She goes to dinner with Victor Aldertree to distract him, while Aline searches for more information.
Jonathan reveals that the sword can only be used by someone with Morgenstern blood.
Raphael is taken away by the guards and Simon is electrocuted trying to stop them. He wakes up face to face with a half Seelie, half Shadowhunter who has taken his ring.
Clary realizes the reoccurring nightmare she had as a child was a vision of Jonathan.
Simon sneaks away and searches for Raphael. Once he finds him, he discovers he's no longer a vampire.
Aline reveals to Isabelle that the Clave has been injecting Downworlders with Heavenly Fire to make them human. Victor is planning to slip it into the city's water supply.
Simon and Raphael escape and retrieve the Heavenly Fire with the help of the half Seelie guard, who introduces herself as Helen Blackthorn. They blow up Aldertree's operation.
Victor Aldertree is arrested.
Clary tells Jonathan they have a way to get rid of their twinning rune.
Alec's plan to propose to Magnus goes awry when Magnus shows up to dinner drunk and breaks down in his arms.